Carbureter.



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s'mfrEs PA, i NT'oF I'oE.

BITTER, OF CHICAGO, ILLINOIS, ASSIGNOR T0 STROMBERG MOTOR DEVICES COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

CARBURETER.

Specification of Letters Patent.

Patented Dec. 5, 1916.

' Application filed January 12, 1914. Serial No. 811,533.

To all whom it may concern:

Be it known that I, GEORGE F. BITTER, a citizen of the United States, residing at Chicago, in the county of Cook and Stateof Illinois, have invented certain new and usefulv Im rovernents in Carbureters, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to an improved carburetor of the compensating type in which provision is made for maintaining a fuel mixture of uniform richness for varying speed conditions of the engine supplied with fuel by said carbureter.

It is well-known in the art that a simple single jet carbureter will not supply a mixture of uniform richness for varying speeds of the engine, but that the mixture becomes richer as the speed of the engine and, therefore, the demand upon the carbureter, in-

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iary air. valve, as a result ofwhich it will open and close according to the demand made upon the carbureter by the engine and for any given running condition it will re' main practically quiet in such a position as to permit the proper amount of air to pass through it for the running condition of the engine then obtaining.

The several drawings illustrating my invention are as follows:

Figure 1 shows my carburetor construction in vertical sectional view, the float chamber being shown in vertical elevation. Fig. 2 is a sectional view of the parts shown in Fig. 1. taken along the line 22. Fig. 3 is a top view of a control cam for the auxiliary air valve, taken along the line 33 in Fig. 1. Fig. 4 shows, in a view similar to Fig.1, a modified construction -of carbureter'in which a sing jet is e ployed of such a construction as to compensate for varying conditions of operation.' Fig.' 5 shows, in a view similar to Fig. 4,'an enlarged vertical sectional view of the fuel jet used in Fig/1.

Similar numerals refer to'similarparts throughout the several views Referring to the drawings, the carburet'er consists of a main casin 1 connecting at its lower end with the mam air supply passage 2 controlled by an intake throttle valve 3, of the butterfly type, operatedby a crank l by means of a connecting rod 5 extending to any desired point of control, as, for example, the dashboard of the vehicle when the carbureter is used in connec tion with an automobile engine. Centrally disposed in the body of the air passage extending vertically throu 'h the casing 1 1s a Venturitube 6 provi ed to increase the velocity of the air at this point to produce' a proper aspiratingeffect upon the fuel nozzle 7. ThlS nozz e is mounted in an upwardly extending arm from the cross rib 8 extending across the lower end of the main air passage through the carbureter,

and this rib is extended beyond the wall of the casing 1 to support a float chamber 9 which supplies the carbureter with -fuel.- The particular mechanism of the float chamlene, is supplied to the float chamber 9 by the supply connection 10 and communication is established between the float chamber and the nozzle or jet 7 by means of holes 11 and 12 drilled through the rib 8 and the arm extending upwardly therefrom, the hole 11 being extended beyond the hole 12 into the lower end of a vertical hole or passageway 13 disposed at one side of the Venturi tube and main air passageway to supply fuel to the auxiliary nozzle or jet 14:. The mechanism of the float chamber 9 is so designed and adjusted as to maintain the level of the liquid fuelin the float chamber just below the top or upper end of the nozzle 7, at substantially the level indicated by the broken line 15-16. The hole 12 is extended downward beyond the hole 11 through a downwardly projecting extension member from the rib 8, through the casing of the carbureter and communicates at it tion on said rod. An operatingrod 31 is lower end with a pet-cock 17 for draining the gasolene from the float chamber and carbureter when desired, the normal condi tion of this pet-cock during operation of the engine beingclosed.

The nozzle 14 projects into anair passage 18 extending to one side from the main air passageway through the carburetor within an extension 19 formed from the side wall of the casing 1 of the carburetor. A spider 20-extends into the top surface of the extension 19 so that it is in substantially horizontal position, and this spider carries a central boss 21 drilled vertically to receive the vertical guide rod22 0f the auxiliary without allowing any substantial clearance between the moving parts. The receptacle 25 has projecting from its bottom a boss 26 drilled to support a rod 27 so that it may be freely moved vertically in said boss by a cam 28 pivotally connected to a vertical rod 29 rigidly securedin a boss 30 extending from the bottom of the receptacle 25, as illustrated. A coller 30 secured to the lower end of rod 29 holds the cam 28 in posipivoted "to a leverj32 extending to the left of the rod 29 from the cam 28 so that the cam may be controlled from any distant point as desired.

The upper end of the rod 27 carries a circular block 33 having a central yertical bore to freely receive the lower end of the 'end of the block 33.

rod 22, and this block has formed upon it a shoulder 34 upon which athe-lower end of the spring35 rests, the upper end of this spring being in engagement with the lower surface of the valve '23 inside of the tubular extension 24: A second spring 36 is located inside of the spring 35 with its upper end resting against the shoulder 37 projecting from the lower surface of the valve 23, and its lower end resting against a flanged collar 38 secured to the rod 22 above the upper When the cam is turned the tension of the two springs may be successively. increased. The receptacle 25 has drilled through its sidewalls, just above the bottom of said receptacle, a plurality of holes 39 so that theinside of the tubular extension is subjected at all times to substantially atmosphereic pressure; and

the portion of the lowersurface of the valve 23 outside of the tubular'extension 24c is subwith the large upper surface of air valve 23,

jected to the suction developed injthe air passage 18 by therunning of the engine. As a result of this, any desired degree of differential action may be secured so that" P which is found desirable in ractice, the amount of surface exposedto t e suction or partialvacuum created inthe passageway'18 may be of any desired extent and by correspondingly proportioning the springs 35 and 36 any desired amount of opening may be secured for a given increasein-the partial vacuum found in the air passage 18 'for different running conditions of the-engine. To regulate the operation of the valve, a 8 spring stop 40 engaging notches 41 in. the edge of the spider 20 is provided, so that by turning the spider 20 thetension upon the spring 35 may be varied without, however, changing the initial tension on the 8 spring 36 since the rod 22 moves verticallywith the spider 20 when the latter is adjusted. An independent adjustment of the spring 36 may be effected by manipulating the milled head 42 on the upper end of the 9 rod 22. The rod 22 is slidably mounted in the boss 21 and is supported bythe engagement of the milled head 42 upon thetop of thee boss. Since the milled head 42 is threaded upon the rod 22, it maybe adjust- 9 ed relative to the rod, and the collar 38 raised or lowered, as desired. The head 42 is provided with a downwardly extending spline pin 42', which is adapted to'engage 111 a corresponding pocket in the boss 21, as 1 illustrated in Fig. 1.. This, engagement of the spline pin in the pocket holds the head 42against rotation and therefore prevents the. head from being jarred out of adjust ment. When it is desired to adjust the 1 height of the collar 38, the head 42 is raised so as to bring the pin out of the pocket and is then turned to the desired extent and then lowered. so as to return the pin to the pocket. I

It will be vobvious that if the collar 38 is sufficiently lowered, the top of the spring 36 may be spaced away from the under side of the valve. In such a case, whatis known as a pick up action is secured 1 that is, on the lower speeds the spring 35 constitutes the entire resistance to the open ing of the valve, whereas on the higher speeds the valve islowered sufiiciently to bring the spring 36 into additional resistance.

The auxiliary nozzle 14being located in the path of the air supplied to the carbureter through the auxiliary valve 23 serves to supply to the carbureter asufii- 1 cient amount of fuel by its aspirating action so that the combinedmixture formed in the upper part of the carbureter and supplied to the engine from the two air passages and the two nozzles will have a. uniform rich-.1

play to form an 1' nessfor varying speeds of engine operation and correspondingly varying degrees of suction produced by the engine. The auxiliary nozzle 14 is provided with a small opening 43 communicating with an air passageway 44 extending through the horizontal wall 45 which supportsthe Venturi tube 6. 'The passageway 44 communicates with the atmosphere through a hole 46 formed in the side wall of the carbureter casing, and the wall 45, being continuous, afi'ords no passage for the incoming air from the passageway 2 except through the" Venturi tube 6.

-A clearance opening is provided around the nozzle 14, opposite the hole 43, which clearance opening is in connection with the passageway 44 so that the interior of the nozzle 14 is inc'ommunication with the atmosphere for any angular position of the hole 43. This provides that the hole 43 need not be disposed in any particular angular position in the nozzle to line up with the opening 44 when the nozzle is screwed securely against its seat. The nozzle opening and the hole 43 are so proportioned that for the amount of suction or partial vacuum created in the upper part of the carbureter during starting conditions and ,low running speeds of the engine, the air entering the nozzle 14'through the hole 43will serve to nearly orquite prevent the supply of gasolene'from the nozzle 14 to the air passing through the. carbureter for these conditions. When the valve 23 is opened, however, by an increase in the suction produced in the carbureting chamber, the aspirating action resulting from the rush of air' across the end of the nozzle 14 sucks out the contents of the nozzle more rapidly than air can be supplied to the nozzle through the hole'43, as a result of which gasolene is supplied by the nozzle 14 in such quantity, owing to the relation between the bore of the nozzle and the size of the hole 43 that the combined mixture produced in the carbureter will have a substantially uniform richness for varying demands made by the engine. A throttle valve of the ordinary butterfly type is disposed in the upper part of the mixing chamber of the carbureter to determine the amount of fuelmixture supplied by the carbureter to the engine for varying conditions of load carried by the engine.

tinued for slow speeds of the engine, after which, as the engine increases 1n speed, the

increased suction opens the air valve 23 an amount depending upon the said ncrease. Thereupon the inrushing air passlng over the valve 23 will tend to keep the valve in substantially the same position for the particular running condition of the engine then tively small amount of surface of the valve 23 exposed to the suction of the engine, the springs 35 and 36 may be made comparatively light. and the inertia of the valve will, therefore, tend to prevent its ready fluctuation or fluttering for the pulsations in the suction caused by the operation of the engine. In this way the adjustments may readily be made such as to take care of any desired operating conditions. If, during any condition of operation, it is found that a richer mixture is required for a short time than is supplied by the open position of the auxiliary air valve, the cam 28 is operatedso asto move the block 33 upward, increasing the tension upon the spring 35 and bringing the block into engagement with the lower end of the rod 22 to hold the valve 23 securely against its seat. By moving the cam 28 a small amount, it will be nozzle 7 is of such a conformation thatthe fuel flow therethrough varies in a manner to compensate for the varying degrees of suction .produced in the carbureting chamher, so that the mixture becomesleaner for increasing engine speeds. The nozzle 7, as shown in Fig.5, is constructed with a Venturi tube delivery opening 7 by which the quantity of fuel flowing through the nozzle is caused to have an entirely different law of variation for varying suctions inthe carbureting chamber from that which obtains with the regular, form of nozzle shown in Fig. 1'. As a result, it is found that with this Venturi tube construction of fuel nozzle,

the fuel delivered for low suction in the carbureting' chamber is of sufiicient quantity to produce a rich mixture which is desirable for starting and for slow speeds of operation. When, however, the suction is increased by an increase in the engine speed, the fuel flowing from the nozzle is increased in quantity in a greater proportion than would result from the use of a plain nozzle, owing to the Venturi tube at the discharge end of the nozzle, and therefore a richer mixture is the result, which is a condition to be desired. This'result is not accomplished wholly by the air flowing through the main airpassages 2 and 6, but by the air passing through these passages in addition to the air passing through the auxiliary air passage 18, which auxiliary passage is controlled in the same manner as described above for the construction shown in Fig. 1.

The effect of the Venturi tube fuel jet is therefore to deliver an amount of fuel which increases;to a greater degree than the introduced through the air passage 18, a progressively leaner mixture is the result as the engine speed lncreases. As a result of this construction, by'properly proportioning the fuel jet for the particular demands to be made upon the carbureter, all complication resulting'from the use of an auxiliary fuel nozzle is done away with, and a much simpler and equally as efiective construction is the result. Furthermore, with the Venturi tube form of nozzle the advantageis secured that suflicient fuel is delivered to the carbureter to produce a proper mixture for high speed operation with a larger quantity of air than could be properly carbureted for the same speed of engine with an auxiliary nozzle of the plain jet type shown inFig.

1, assuming that said nozzles are both constructed to properly carburet the same given volume of air for slow speed operation.

lVhile I have shown myinvention in the particular embodiment herein described, I do not, however, limit myself to this construction and exact arrangement of parts as I may employ other and equivalent constructions without departing from the spirit of my invention.

What I claim is: g Y 1. In a carbureter, the combination of a casing, said casing containing a mixing chamber and having a main and an auxiliary air passage for sup-plying air thereto, and a valve for said auxiliary passage having a part of one of its surfaces subject to the pressure in said auxiliary passage and theremainder of the same surface subjected to substantially atmosphericpressure.

2. Ina carbureter, the combination of a casing, said casing containing amixing chamber and having a main and an auxiliary air passage for supplying air thereto,

a valve for said auxiliary passage havinga part-of one of its surfaces subject to the pressure in said auxiliary passage and. the

remainder of the same surface subjected to substantially atmospheric pressure, and a spring-for normally holding said valve in its closed position.

3. In a carbureter, the combination of a casing, said casing containing a .mixing chamber and having a main and an auxiliary air passage for supplying air thereto,

a valve for said auxiliary passage having a part of one of its surfaces, subject to the pressure in said auxiliary passage and the remainder of the same surface subjected to substantially atmospheric pressure, a spring for normally holding said valve in its closed position, and devices for holding said valve in its closed position when desired.

4:. In a carbureter, the combination of a casing, said casing containing a mixing.

casing, said casing containing a mixing chamber and having a main and an -auxil-- iary air passage for supplying air thereto, and a valve for said auxiliary passagehav- .ing a cylindrical extension; from one of its faces through said auxiliary passage to cooperate with a bore in the casing for freely receiving said extension whereby the cylindrical surface of the extension and the adj acent surface of the valve outside of said extensionare subjected to the pressure in the auxiliary passage and the portion of the valve within the cylindrical extension is subjected to substantially atmospheric pres sure.

casing, said casing containing a mixing chamber and having a main and an aux1l- 1ary alr passage for supplying air-thereto,

cylindrical extension fromone of its faces through said auxiliary passage to cooperate sion are subjected to the pressure in theauxiliary passage and the portion of the valve within the cylindrical extension is subjected to substantially atmospheric pres- 6. In a carbureter, the combination of' a avalve for said auxiliary passage having a sure, and a spring for normally holding said valve in its clo'sedposit-ion. v

7 In a carbureter, the combination of. a

through said auxiliary passage to cooperate with a bore in the casing for freely-receivcasing, said casing containing a mixing ing said extension whereby the cylindrical surface of the extension and. the adjacent surface of the valve outside of said extension are subjected to the pressure in the auxiliary passage and the portion of the subjected to substantially atmospheric pressure, a spring for norma y holding Sa d valve within the cylindrical extension is valve in its closedposition, and mechanism for holding said valve, in its closed position when desired.

8. In a carbureter, thecombination of a casing, said casing containing a mixing chamber and having a main and an auxiliary air passage for supplying air thereto, a valve for said auxiliary passage having a cylindrical extension from one of its faces through said auxiliary passage to cooperate with a bore in the casing for freely receiving said extension whereby the cylindrical surface of the extension and the adjacent surface of the valve outside of said extension are subjected to the pressure in the auxiliary passage and the portion of the valve within the cylindrical extension is subjected to substantially atmospheric pressure, two springs engaging said valve to oppose the opening thereof, and independent mechanism for adjusting the tension of each spring. a

9. In a carbureter, the combination of a casing, said casing containing a mixing chamber and having a main and an auxiliary air passage for supplying air thereto, a valve for. said auxiliary passage having a cylindrical extension from one ofits faces through said auxiliary passage to cooperate with a bore in the casing for freely receivingsaid extension whereby the cylindrical surface of the extension and the adjacent surface of the valve outside of said extension are sub jected to the pressure in the auxiliary passage and the portion of -the valve within the cylindrical extension is subjected to sub stantially atmospheric'pressure, two springs engaging said valve to oppose the opening thereof, and independent mechanism for adjusting the tension of each spring, said cylindrical extension being counter-bored to receive the ends of said springs.

10. In a carbureter, the combination of a casing, said casing containing a mixing chamber and having a main and an aux iliary air passage for supplying air thereto, a valve for said auxiliary passage having a cylindrical extension from one of its .faces through said auxiliary passa e to cooperate with a bore in the casing for'g'eely receiving said extension whereby the cylindrical surface of the extension and the adjacent surface of the valve outside of said extension are subjected to the pressure in the auxiliary passage and the portion of the valve within the cylindrical extension is subjected to substantially atmospheric pressure, and a cup carried by the casing for receiving said cylindrical extension, said cup having one or more air openings. near itslower end.

11. In a carbureter, the combination of a casing, said casing containing a mixing chamber and having a main and an auxiliary air passage for supplying air thereto a valve for said auxiliary passage having a cylindrical extension from one of its faces through said auxiliary passage to cooperate with a bore in the casing for freely receiving said extension whereby the cylindrical surface of the extension and the adjacent surface of the valve outside of said extension are subjected to the pressure in the auxiliary receiving said cylindrical extension, said cup e havingone or'more air openings near its lower end.

12. In a carburete'r, the combination of a casing, said casing containing a mixing chamber and having a main and an auxiliary air passage for supplying air thereto, a valve for said auxiliary passage having a cylindrical extension from one of its faces through said auxiliary passage to cooperate with a bore in the casing for freely receiving said extension whereby the cylindrical surface of .the extension and the adjacent surface of the valve outside of said extension are subjected to the pressure in the auxiliary passage and the portion of the valve within the cylindrical extension is subjected to substantially atmospheric pressure, a spring for normally holding said valve in its closed position, mechanism for holding said valve in its closed position when desired, and a cup carried by the casing for receiving said cylindrical extension, said cup having one or more air openings near its lower end.

13. In a carbureter, the combination of a casing, said casing containing a mixing chamber and having a main and an auxiliary air passage for supplying air thereto, a valve for said auxiliary passage having a cylindrical extension from one ofits faces through said auxiliary passage to cooperate with a bore in the casing for freely receiving said extension whereby the cylindrical surface of the extension and the adjacent surface of the valve outside of said extension are subjected to the pressure in'the auxiliary passage and the portion of the valve within the cylindrical extension is subjected to substantially atmospheric pressure, two springs engaging said valve to oppose the opening thereof, independent mechanism for adjusting the tension of each spring, and a cup carried by the casing for receiving said cylindrical extension, said cup having one or more air openingsen'ear its lower end.

14;. In a carbureter, the combination of a casing, said casing containing a mixing chamber and having a main and an auxiliary air passage for supplying air thereto, a valve-for said auxiliary passage having a cylindrical extension from one of its faces through said auxiliary passage to cooperate with a bore in the casing for freely receiving said extension whereby the cylindrical surdrical extension being counter-bored to re:

ceive the ends of said springs, and a cup carried by the casing for receiving said cyli'ndrical' extension, said cup having one or more air openlngs near its lower end.

15. In a carbureter, the combination of a casing containing a mixing chamber and having an air passage leading thereto, and a valve for said passage having apart of one of its, surfaces subject to the pressure in said passage and the remainder of the sa'me surface subjected to substantially atmospheric pressure. 7

16. In a carbureter, the combination of a casing containing a mixing chamber and having an air passage leading thereto, and

a valvefor said passage having a cylindrisz cal extension from one of its faces through said passage whereby the cylindrical surface of the extension and the adjacent surface of the valve outside of. said extension are subjected to the pressure in said passage and the 'portion of 'the valve within the-cylindrical extension is subjected to substantially atmospheric pressure.

17 In a carbureter, the combination of a casing contalnlng a mixing chamber and having an ,air passage leading thereto, a

valve for said passage having a cylindrical extension from one of its faces through said passage whereby the cylindrical surface of the extension and the adjacent surface of the valve outside ofsaid extension are subj ected to the pressure in saidpassage and the portion of the valve within the cylindrical extension is subjected to substantially atmospheric pressure, and a cup carried by said casing for receiving said extension, said cup having one or more air openings through it near the bottom thereof.

18. In.a carburet'er, the combination of a casing containing a mixing chamber and having an air passage leading thereto, a

valve for said passage having a part of one of itssurfaces subject to the pressure in said passage and the remainder of the same surface subjected to substantially atmospheric pressure, and a spring for normally holding the valve in its closed position.

19. In a carbureter, the combination of a casing containing a mixing chamber and having an air passage leading thereto, a

valve for said passage having a cylindrical extension from one of its faces through said passage whereby the cylindrical surface of the extension and' the adjacent surface of the valve outside of said extension are subjected to the pressure in said passage and the portion of the valve within the cylindrical extension is subjected tov substantially atm0spheric pressure, and a cup carried by said casing for receivingsaid extension, said cup having one or -more air openings through it near the bottom thereof.

20. In a carburete-r, in combination, a chamber in which. reduction in pressure is produced, an air inlet leading t9 said chamber, fuel-inlet means, and a valve in said air inlet, said valve having one face exposed to the atmosphere and a portionvof the other face exposed to the pressure in said chamher, the remainder of said second-named face being exposed to the atmosphere.

In witness whereof, I hereunto subscribe my name this 8th day of January, A. l).

. GEORGE-F. BITTER. Witnesses:

ALBERT C. BELL, LESLIE WV. 'FRICKE. 

